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A word about power supplies

Fortunately, I already had a replacement (a Corsair 430W Modular - and I wish it wasn't modular, because that made it a pain-in-the-ass to install).

There was a minor panic when it didn't work - then I realise the fuse in the cable probably went so changed to the new cable too and voila - all appears well (phew and double phew).

I make this post for a number of reasons tho

1 - to remind people that a spare PSU is a bloody good idea
2 - to remind people that there's a LOT to go bang inside a PSU.
3 - to remind people to check the fuses in their power cables

Why 3? Well the fuse blew in the cable because it was 5a - which is correct, I believe. Thing is, tho, I tested the PSU once removed, using a stock cable, and it repeated it's "blue-bang-flash-pop" but this time MUCH worse. I reckon that's because that cable had a 13a fuse in it (which didn't blow - tho the house circuit tripswitch did!!)

So check your plugs - if they're more than 5a fused, put a 5a in there (unless you're PSU is mysteriously using more than that?) and you will be protecting your kit a bit better.

It was a Gigabyte 460W - it's been in this PC for the big-end of 3 years but it actually came to me as a warranty replacement back in 2008 and it spent it's first 2 years going between PCs and the 'spares shelf' quite a bit.

Can't really complain - it's just over 5 years old and all - and it seems to have constrainted it's explosion to itself (and the cable fuse and the house tripswitch!!) and not fried the rest of my PC - which is nice of it.

ANY attempt to plug it in results in a a fireworks show tho - so it's off to the skip...

This Corsair modular I've replaced it with was a bad choice perhaps tho - it has a THICK fixed cable for the Mobo+Cpu and 4 'modular' cables which are

2xSATA (closely spaced)
2xSATA (closely spaced)
1xPCI
2xMOLEX+FDD

Which means in almost ANY PC you'll be plugging-in 3 and I need all 4 (SATA drives widely spaced and I have a PATA DVD which needs a molex) and that all makes for FAR FAR more cable than you'd have in a non-modular design. I'm even tempted to use a MOLEX-SATA to get rid of one of them...

or it's going back in the box when I source a replacement for it - I'll fob-it-off on someone - wanted, 450Wish PSU with a long/wide spaced 4xSATA, 1 MOLEX, 1 PCI - only needs a 4-pin CPU (the 8pin on this Corsair is a TIGHT fight against a capacitor too) too :)

It is QUIET tho - MUCH quieter than the old Gigabyte, esp under load (when it's barely any different to when it's not)

Why 3? Well the fuse blew in the cable because it was 5a - which is correct, I believe. Thing is, tho, I tested the PSU once removed, using a stock cable, and it repeated it's "blue-bang-flash-pop" but this time MUCH worse. I reckon that's because that cable had a 13a fuse in it (which didn't blow - tho the house circuit tripswitch did!!)

I think the fuses in power cables is a British thing. They're not in the Schuko plugs we use.

As to the OP: it's sound advice. The first thing one should do when choosing a PSU is research the thing, and the easiest way to do that is to go to the forum of a well-trafficked hardware enthusiast site, find the PSU subsection (if they don't have one, look elsewhere), and ask for a recommendation in your price range. Be prepared to pay around 50 USD for a well-built unit unless it's on sale (but note that 50 USD exchanged into other currencies may not be generally indicative of quality given that markets vary considerably by region).

The second thing to do is as Sakkura suggests: take some canned air to the unit every 6 months or so (and more often if the unit is in a super-dusty environment like a shop). Clean off the heatsinks and fans and any places with accumulated funk. Canned air is super cheap and super-dry, but you could also get cheap pancake or drum air compressors (which have many other useful applications besides cleaning out electronic devices). With a compressor you'd want to make sure you're not using so much pressure that you bend soldered components around, and (if you can) hold fan blades in place when cleaning them rather than letting them spin them up (but never stick conductive material into a PSU).

For the record, I use a 'lens cleaning puffer' for cleaning PSUs and heatsinks - I broke-off the 'no suckback' thing as it restricted the airflow too much and now it moves crap from grilles and fans which I can later grab with the vac...

Canned air is cheap but, in all honesty, blowing hard is all you need - it's just you'll end-up swallowing a LOT of crud...

As to the OP: it's sound advice. The first thing one should do when choosing a PSU is research the thing, and the easiest way to do that is to go to the forum of a well-trafficked hardware enthusiast site, find the PSU subsection (if they don't have one, look elsewhere), and ask for a recommendation in your price range. Be prepared to pay around 50 USD for a well-built unit unless it's on sale (but note that 50 USD exchanged into other currencies may not be generally indicative of quality given that markets vary considerably by region).

Even easier way is to google for reviews. Preferably from sites like hardwaresecrets, hardocp, and johnnyguru.

Even easier way is to google for reviews. Preferably from sites like hardwaresecrets, hardocp, and johnnyguru.

Well, Googling "what PSU is the best" produces mostly-useless advice articles and reviews of units which just happen to be popular/relevant. If one doesn't have a unit in mind from the outset, going to an enthusiast forum provides a broad range of people who follow the market and thus know about the best deals at the time (and one can Google specific units from there).

Oh I know, and that's fine. But even if one has something in mind, it won't really hurt (assuming one's at least somewhat discerning) to ask enthusiasts for advice. Even with units that review well, one might get a repair person or enthusiast who says that particular model got some component revision and current units should be avoided (or x_unit is on sale right now, or whatever).

Are the PSU calculators suggesting the minimum PSU you should buy, or the actual power needed? Because a lot of cheaper PSUs can't provide their rated power continuously. There's efficiency to consider too, though I'm not sure how that tends to work with regards to PSU labelling. Would an 80% efficient 300W PSU draw 375W to provide 300 or draw 300 to provide 240?

So PSU rails then - it seems that most PSUs under 500W are single rail but a few other multiple rails?

Any real reason to care about that? I don't overclock and I'm WAY under the 450W requirement (realistically I think I need 320W at worst)

In a PSU from a crappy brand, multiple 12V rails could be a problem in some situations. But in any halfway decent PSU it doesn't matter. If anything, multiple rail design means slightly more safety for your components (because it's easier to trip a smaller rail than a big combined one).

Originally Posted by trjp

Out of curiousity, I hooked-up to a plug-in Watt Monitor earlier today and I've been looking at it's data...

PSU Calculators suggest I need a min. of 280W and recommend 330W (tho none support my 650 TI Boost which is lower-power than the 650TI they offer me instead).

Reality is that my system idles at just 65W! and gaming hasn't pushed-it over 180W yet...

I stopped putting this PC to sleep overnight as would, occasionally, BSOD on waking (a driver problem most likely) - but at that level of usage I don't even need to turn it off!!

The Sky Box downstairs uses more juice :)

Well, give it a go with Prime95 and Furmark running, if you want to see what it's capable of drawing in a worse-than-worst case scenario.

Are the PSU calculators suggesting the minimum PSU you should buy, or the actual power needed? Because a lot of cheaper PSUs can't provide their rated power continuously. There's efficiency to consider too, though I'm not sure how that tends to work with regards to PSU labelling. Would an 80% efficient 300W PSU draw 375W to provide 300 or draw 300 to provide 240?

PSU calculators are inaccurate and usually have a built-in safety margin so you can buy a PSU rated at what they suggest.

Reliable brands label their PSUs for what they can deliver continuously to the components. The power lost in the PSU itself isn't factored in, so efficiency is irrelevant to capacity (but lower efficiency will mean more heat generated in the PSU, which will need more cooling to avoid shortening its lifespan). So an 80% efficient 300W PSU would draw 375W to deliver 300W to the components.

My psu got really noisy after a dust build up. Put my tower upside down turned my fan the drags air past my hdd and pushes it into my psu in its "tunnel" (antec 120 case) and blocked off some holes that were compromising the thermal ducting and it quietened down. What I really need is a can of compressed air to blitz it with.

Regularly vacuum and air dust everything in your case.
I once saw a 10c drop in temp on my cpu after using a soft paintbrush to clean the fan fins!
My old Themaltake 500w benefited from doing this often. My lovely new GS800 doesn't start the fan 'till it's under an awful lot of load and seems to keep itself cleaner.